> ## Documentation Index > Fetch the complete documentation index at: https://docs.base44.com/llms.txt > Use this file to discover all available pages before exploring further. > ## Agent Instructions > Internal links on these pages omit the .md extension. Append .md to a docs page URL, or send an Accept: text/markdown header, to get that page as markdown. # Update comment anchor > This API is in beta. Endpoints, fields, and behavior may still change, so avoid depending on it in production. Moves a thread's pin and replaces its screenshot. Only the person who started the thread can do this. `anchor` pins the thread to an element of the app's preview. The builder fills it in when you click an element, and `source_location` must match that element's `data-source-location` attribute in the preview for a pin to show. Leave `anchor` out to post a thread with no pin. It still shows in the builder's comments panel. The `anchor` you send replaces the old one in full. Send `screenshot_file_uri` to attach a new screenshot, or leave it out or send `null` to remove the screenshot. To attach a screenshot, upload the image with [Upload app file](/api-reference/upload-app-file) and `visibility` set to `private`, then pass its `file_uri` as `screenshot_file_uri`. Only private files uploaded to this app are accepted. Anyone with the app open in the builder sees the change right away. This is limited to 120 requests per minute per app, shared by every other comments endpoint. A signed-in session has its own limit, and every personal access token for the workspace shares one. Some workspaces have a different limit. Every request that counts against the limit gets `X-RateLimit-Limit`, `X-RateLimit-Remaining` and `X-RateLimit-Reset` (Unix time in seconds) headers, and a `429` also gets `Retry-After` in seconds. If the limiter itself is unavailable, requests go through without these headers. Call this as an editor of the app, with a personal access token sent as a Bearer token or from a signed-in session. Viewers in the app's workspace, read-only tokens, and workspace API keys are refused. The response includes fields beyond the ones documented here. Don't rely on undocumented response fields, as they can change at any time. ## OpenAPI ````yaml /developers/references/app-management/app-management-openapi.json patch /api/apps/{app_id}/comments/threads/{thread_id}/anchor openapi: 3.1.0 info: title: Base44 App Management API version: 1.0.0 servers: - url: https://app.base44.com security: - PersonalAccessTokenAuth: [] paths: /api/apps/{app_id}/comments/threads/{thread_id}/anchor: patch: summary: Update comment anchor description: >- This API is in beta. Endpoints, fields, and behavior may still change, so avoid depending on it in production. Moves a thread's pin and replaces its screenshot. Only the person who started the thread can do this. `anchor` pins the thread to an element of the app's preview. The builder fills it in when you click an element, and `source_location` must match that element's `data-source-location` attribute in the preview for a pin to show. Leave `anchor` out to post a thread with no pin. It still shows in the builder's comments panel. The `anchor` you send replaces the old one in full. Send `screenshot_file_uri` to attach a new screenshot, or leave it out or send `null` to remove the screenshot. To attach a screenshot, upload the image with [Upload app file](/api-reference/upload-app-file) and `visibility` set to `private`, then pass its `file_uri` as `screenshot_file_uri`. Only private files uploaded to this app are accepted. Anyone with the app open in the builder sees the change right away. This is limited to 120 requests per minute per app, shared by every other comments endpoint. A signed-in session has its own limit, and every personal access token for the workspace shares one. Some workspaces have a different limit. Every request that counts against the limit gets `X-RateLimit-Limit`, `X-RateLimit-Remaining` and `X-RateLimit-Reset` (Unix time in seconds) headers, and a `429` also gets `Retry-After` in seconds. If the limiter itself is unavailable, requests go through without these headers. Call this as an editor of the app, with a personal access token sent as a Bearer token or from a signed-in session. Viewers in the app's workspace, read-only tokens, and workspace API keys are refused. The response includes fields beyond the ones documented here. Don't rely on undocumented response fields, as they can change at any time. operationId: >- update_app_comment_anchor_api_apps__app_id__comments_threads__thread_id__anchor_patch parameters: - name: app_id in: path required: true schema: type: string description: ID of the app. title: App Id description: ID of the app. example: 6820f3a4e7b91d003c45a1f2 - name: thread_id in: path required: true schema: type: string description: >- ID of the comment thread, from `thread.id` in [List comments](/api-reference/list-comments). title: Thread Id description: >- ID of the comment thread, from `thread.id` in [List comments](/api-reference/list-comments). example: 68e2b7c1d4f0a9001c3e5a17 requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/UpdateAnchorPayload' responses: '200': description: The thread with its new pin. content: application/json: schema: $ref: '#/components/schemas/CommentThread' '400': description: '`screenshot_file_uri` isn''t a private file uploaded to this app.' '401': description: Missing or invalid credentials. '403': description: >- You don't have editor access to this app, you're a viewer in the app's workspace, the app is blocked, or your token is read-only or a workspace API key, or you didn't start this thread. '404': description: App or comment thread not found. '409': description: Your workspace requires an unlocked SSO session. '422': description: Validation Error content: application/json: schema: $ref: '#/components/schemas/HTTPValidationError' '429': description: >- Rate limit exceeded. Wait the number of seconds in `Retry-After` before retrying. components: schemas: UpdateAnchorPayload: properties: anchor: $ref: '#/components/schemas/CommentAnchor' description: The thread's new pin. It replaces the old one in full. screenshot_file_uri: anyOf: - type: string maxLength: 2000 - type: 'null' title: Screenshot File Uri description: >- `file_uri` of a screenshot uploaded to this app with [Upload app file](/api-reference/upload-app-file) and `visibility` set to `private`. Starts with `mp/private/` followed by the app's ID. example: mp/private/6820f3a4e7b91d003c45a1f2/4b1e9c2a7_shot.png type: object required: - anchor title: UpdateAnchorPayload description: A thread's new pin and screenshot. CommentThread: properties: id: type: string title: Id description: ID of the thread. example: 68e2b7c1d4f0a9001c3e5a17 page_path: type: string title: Page Path description: Path of the app page the thread is on. example: /pricing anchor: $ref: '#/components/schemas/CommentAnchor' description: Where the thread is pinned in the app's preview. screenshot_url: anyOf: - type: string - type: 'null' title: Screenshot Url description: >- Signed link to the screenshot attached to the thread, valid for one hour. `null` when the thread has no screenshot or it can't be read. example: >- https://static.base44.com/images/private/6820f3a4e7b91d003c45a1f2/4b1e9c2a7_shot.png?token=eyJhbGciOi resolved_at: anyOf: - type: string format: date-time - type: 'null' title: Resolved At description: When the thread was resolved, in UTC, or `null` while it's open. example: '2026-10-05T09:14:22.512000Z' message_count: type: integer title: Message Count description: Number of replies, not counting the first comment. example: 2 last_activity_at: anyOf: - type: string format: date-time - type: 'null' title: Last Activity At description: When the thread was created or last replied to, in UTC. example: '2026-10-05T09:14:22.512000Z' created_date: type: string format: date-time title: Created Date description: When the thread was created, in UTC. example: '2026-10-05T09:14:22.512000Z' agent_working_since: anyOf: - type: string format: date-time - type: 'null' title: Agent Working Since description: >- When the builder agent started working on the thread, in UTC, or `null` when it isn't working on it. A value older than an hour is left over from a turn that stopped. example: '2026-10-05T09:14:22.512000Z' unread: type: boolean title: Unread description: >- Whether the thread has a comment from someone else posted after you last read it. Always `false` in the responses of Create comment and Update comment anchor. example: true type: object required: - id - page_path - anchor - screenshot_url - resolved_at - message_count - last_activity_at - created_date - agent_working_since - unread title: CommentThread description: A comment thread's state. HTTPValidationError: properties: detail: items: $ref: '#/components/schemas/ValidationError' type: array title: Detail type: object title: HTTPValidationError CommentAnchor: properties: source_location: anyOf: - type: string maxLength: 512 - type: 'null' title: Source Location description: >- Position of the element's tag in the app's code, as `file:line:column`, exactly as the element's `data-source-location` attribute in the preview. The pin shows only on an element with this value. `null` for a thread with no pin. example: pages/Pricing.jsx:42:8 element_tag: anyOf: - type: string maxLength: 64 - type: 'null' title: Element Tag description: HTML tag of the element, such as `button`. example: button instance_index: anyOf: - type: integer minimum: 0 - type: 'null' title: Instance Index description: >- Which of the elements sharing `source_location` the pin is on, counting from `0` in page order, for an element repeated in a list. `null` means the first. example: 0 point: anyOf: - $ref: '#/components/schemas/CommentAnchorPoint' - type: 'null' description: >- Where on the element the pin sits. `null` puts it at the middle of the top edge. crop: anyOf: - $ref: '#/components/schemas/CommentAnchorCrop' - type: 'null' description: >- Area of the page the screenshot shows, used to redraw the crop box in the builder. region: anyOf: - $ref: '#/components/schemas/CommentAnchorRegion' - type: 'null' description: Area of the visible preview the screenshot shows when it was taken. viewport_size: anyOf: - $ref: '#/components/schemas/CommentAnchorViewportSize' - type: 'null' description: Size of the preview when the screenshot was taken. type: object title: CommentAnchor description: >- Where a comment thread is pinned in the app's preview. When the builder's AI edits the anchored file, Base44 moves an open thread's `source_location` to the element's new line. ValidationError: properties: loc: items: anyOf: - type: string - type: integer type: array title: Location msg: type: string title: Message type: type: string title: Error Type type: object required: - loc - msg - type title: ValidationError CommentAnchorPoint: properties: x: type: number maximum: 1 minimum: 0 title: X description: Horizontal position, as a fraction of the element's width. example: 0.5 'y': type: number maximum: 1 minimum: 0 title: 'Y' description: Vertical position, as a fraction of the element's height. example: 0.5 type: object required: - x - 'y' title: CommentAnchorPoint description: Fractions of the anchored element's rect, not of the document. CommentAnchorCrop: properties: x: type: number title: X description: Left edge, in page pixels. example: 512 'y': type: number title: 'Y' description: Top edge, in page pixels, scroll included. example: 1340 width: type: number exclusiveMinimum: 0 title: Width description: Width, in pixels. example: 240 height: type: number exclusiveMinimum: 0 title: Height description: Height, in pixels. example: 96 type: object required: - x - 'y' - width - height title: CommentAnchorCrop description: >- The screenshot's area in page pixels: the visible area plus the page's scroll when it was taken. CommentAnchorRegion: properties: x: type: number maximum: 1 minimum: 0 title: X description: Left edge, as a fraction of the preview's width. example: 0.42 'y': type: number maximum: 1 minimum: 0 title: 'Y' description: Top edge, as a fraction of the preview's height. example: 0.18 width: type: number maximum: 1 minimum: 0 title: Width description: Width, as a fraction of the preview's width. example: 0.2 height: type: number maximum: 1 minimum: 0 title: Height description: Height, as a fraction of the preview's height. example: 0.08 type: object required: - x - 'y' - width - height title: CommentAnchorRegion description: >- The screenshot's area as fractions of the visible preview when it was taken, so it depends on the scroll. CommentAnchorViewportSize: properties: width: type: integer minimum: 1 title: Width description: Width of the preview, in pixels. example: 1280 height: type: integer minimum: 1 title: Height description: Height of the preview, in pixels. example: 800 type: object required: - width - height title: CommentAnchorViewportSize description: Size of the preview when the screenshot was taken. securitySchemes: PersonalAccessTokenAuth: type: http scheme: bearer description: 'Personal access token, sent as `Authorization: Bearer `.' ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.